Although back pain is a highly common and costly disorder, most of the literature has focused on young to middle-aged adults. Preliminary research from this candidate shows that back pain in older persons, severe enough to result in restricted activity (restricting back pain), is both common and frequently episodic. While restricting back pain in older persons is common, much remains to be learned about its impact and burden of suffering in later life. The overall objective of this R03 proposal is to determine, using mixed (quantitative and qualitative) methods, the impact of restricting back pain in older persons. The specific aims of the current proposal are 1) to elucidate the relationship between restricting back pain and subsequent (new or increasing) disability in activities of daily living (ADL) and mobility in older persons and, 2) to explore older persons' perspectives, experiences, and attitudes regarding how restricting back pain impacts daily life from multiple dimensions, including social, physical, and psychological. We hypothesize that a greater number and duration of restricting back pain episodes will be associated with more frequent occurrence of new or increasing disability in ADL and mobility. We anticipate that our qualitative results will provide a more comprehensive understanding of the burden of restricting back pain, in richer detail than what is available from quantitative analyses alone. To accomplish our aims, we will use data from the Yale Precipitating Events Project (PEP), a unique and highly innovative cohort of 754 non-disabled, community-living persons, over the age of 70 at enrollment. Participants have completed comprehensive, home-based assessments at 18-month intervals as well as monthly assessments of restricting back pain and disability for 12+ years. Because certain questions cannot be readily answered using quantitative data alone, we will also conduct in-depth interviews with older persons with restricting back pain to ensure that we capture the range of experiences from the older persons' perspective. Of immediate relevance, our results will provide clinicians, older persons who experience this disorder, and their families, with innovative, novel, and more accurate information that reflects the burden of restricting back pain in older persons. Ultimately, a better understanding of the burden and impact of restricting back pain is a necessary step that may be used to inform development of effective age- and sex-appropriate assessment tools and interventions to improve outcomes of this common condition in older persons.